COSTA MESA, Calif. -- The Los Angeles Chargers and Washington Redskins don't tangle often. But they face off at the StubHub Center on Sunday, Washington's first road game against the Chargers since the 2009 season.

The streaking Chargers (6-6) have resurrected their season after dropping their first four games. They have won three straight and six of the last eight to gain a share of the AFC West lead.

The Redskins (5-7) lost their last time out to the rival Dallas Cowboys. They've lost four of their past six games to all but fall from the NFC playoff race.

The Redskins would likely need to sweep their final month of games in the regular season -- and get some help -- to reach the postseason.

"We do have a 1 percent chance so I'm going to play believing we can do our part, which is four weeks long, and then who knows?" Washington quarterback Kirk Cousins said. "In theory, we still have something to play for and that is enough for me."

The Chargers don't have to crunch the numbers quite as hard to find their path past the regular season. With a share of the lead and games with division rivals Oakland and Kansas City still to come, if they go 4-0 down the stretch, the division is theirs.

That's a long way for a team that lifted the curtain on the season in a new city with four straight losses. That the Chargers are part of the playoff discussion -- after being left for dead -- is among the NFL's biggest surprises this year.

"I am by no means looking that far ahead, but we have a quarter of a season to go," Rivers said. "I think we have a shot, we know that. But we know how quickly it can go the other way.

"We have by no means made it. We got four tough football games ahead of us, starting this week against the Redskins. We are all focused on what is ahead this week and the challenge they present."

The Chargers would seemingly have another cupcake in Washington after getting fat playing the Buffalo Bills, the Dallas Cowboys and the winless Cleveland Browns.

Then again, the Redskins have traveled to the West Coast twice this year and both times came away with impressive wins over the Los Angeles Rams and the Seattle Seahawks.

Those two road wins grabbed Rivers' attention.

"This is a playoff-caliber team and we all know that," he said. "It will be a good challenge for us."

The task at hand for the Redskins is staying interested. But Cousins said he hasn't seen any lack of want-to from his teammates as they near the end of a disappointing season.

"Guys want to play, they are ready to go," Cousins said. "I like the locker room and I like the resiliency. You can see that from what we have been through."

Cousins' front line has been through a lot as Washington continues to shuffle in replacements because of injuries. Considering the Chargers' potent tandem of pass-rushers in Joey Bosa and Melvin Ingram that is an area of concern for the Redskins.

"It definitely starts with those two big names that they drafted in the first round and they have been what they expected them to be," Cousins said, noting the Chargers are No. 5 defending the pass.

"I got to believe a lot of the credit goes go to the pass rush and works back from there. We will have our hands full, as we do every week. The Chargers are no different. But our guards and tackles will have their hands full. It will be a great challenge."

Rivers acknowledges the Chargers have been playing solid and then he eyes the calendar. Veterans know the December football is different from any other month, and the Chargers have to prove they can perform when the stakes are enhanced.

"We have a lot of young guys, and whoever has been here last two years, hasn't had very many meaningful December games," Rivers said. "I think it is good to acknowledge that because it's different, it's exciting and it's what you spend all offseason working on to get into December and have a chance."